Nitride semiconductor structure and semiconductor light emitting device including the same

Abstract

A nitride semiconductor structure and a semiconductor light emitting device including the same are revealed. The nitride semiconductor structure mainly includes a stress control layer disposed between a light emitting layer and a p-type carrier blocking layer. The p-type carrier blocking layer is made from AlxGa1−xN (0<x<1) while the stress control layer is made from AlxInyGa1−x−yN (0<x<1, 0<y<1, 0<x+y<1). The light emitting layer has a multiple quantum well structure formed by a plurality of well layers and barrier layers stacked alternately. There is one well layer disposed between the two barrier layers. Thereby the stress control layer not only improves crystal quality degradation caused by lattice mismatch between the p-type carrier blocking layer and the light emitting layer but also reduces effects of compressive stress on the well layer caused by material differences.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to a nitride semiconductor structure and a semiconductor light emitting device including the same, especially to a nitride semiconductor structure in which a stress control layer made from AlxInyGa1−x−yN is disposed between a light emitting layer and a p-type carrier blocking layer to improve crystal quality degradation caused by lattice mismatch between the p-type carrier blocking layer and the light emitting layer, increase the yield rate, and further reduce effects of compressive stress on quantum well layers. Thus electrons and holes are effectively confined in each quantum well layer and internal quantum efficiency is increased. Therefore the semiconductor light emitting device has a better light emitting efficiency.[0003]2. Description of Related Art[0004]In recent years, light emitting diodes (LED) have become more important in our daily lives due to their broad applications. LED is ...

AI Technical Summary

Benefits of technology

This patent is about improving the quality and efficiency of semiconductor light emitting devices. It introduces a new structure called a stress control layer made of AlxInyGa1−x−yN, which is placed between the light emitting layer and a p-type carrier blocking layer. This layer helps to control the stress and lattice mismatch between these layers, which can lead to crystal quality degradation and decreased yield rates. By reducing the impact of compressive stress on the well layers, the new structure helps to effectively confine electrons and holes in each layer and increase the internal quantum efficiency of the device. This results in better light emitting efficiency.

Problems solved by technology

However, the light efficiency of the LED can be affected by a plurality of factors such as current crowding, dislocation, etc.

Although the carriers can be effectively confined in the quantum well layers by using p-AlGaN as the p-type carrier blocking layer, there is high lattice mismatch between the p-AlGaN p-type carrier blocking layer and the GaN quantum barrier layer.

Thus the InGaN quantum well layers are seriously affected by the compressive stress due to the lattice mismatch.

Moreover, the compressive stress also degrades the adjacent GaN quantum barrier layers and interface properties among the InGaN quantum well layers so that carriers are lost at the interface and the light emitting efficiency of the LED is also affected.

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